Shot cleaning machine

ABSTRACT

A shot cleaning machine of the type wherein shot is cyclically impelled by a rotary impeller to impinge upon the contents of a rotatable reticulated basket, with spent shot being returned to the impeller, with the machine being specially provided with rotary means coupled to the impeller for automatically regulating the rate of return of spent shot to the impeller to be largely a function of the rate of rotation of the impeller so that when the latter is decelerated and stopped the rate of shot fed thereinto is reduced so that the latter does not become so loaded with shot as to become difficult or impossible to restart.

United States Patent Hazlewood 1 Mar. 19, 1974 SHOT CLEANING MACHINE 3,546,816 12/1970 Enegren 51/9 [75] Inventor. 2322M D. Hazlewood, Lindsborg, Primary Examiner Donald G Kelly Assistant ExaminerHoward N. Goldberg [73'] Assignee: Vacu-Blast Corporation, Belmont,

Calif. [57] ABSTRACT [22] Filed; Dec. 7 A shot cleaning machine of the type wherein shot is cyclically impelled by a rotary impeller to impinge [21] Appl' 2087185 Fupon the contents of a rotatable reticulated basket, I with spent shot being returned to the impeller, with 52 US. c1. 51/9, 51/13 the machine being Specially provided with y 51 1m. (:1. B24c 3/14 means coupled to the impeller for automatically regu- 58 Field of Search 51/9, 13, 222/254 lating the rate of return of spent shot to the impeller to be largely a function of the rate of rotation of the 5 References Cited i r npeller so that when the latter is decelerated and UNITED STATES PATENTS v stopped the rate of shot fed thereinto is reduced so p that the latter does not become so loaded with shot as I wil to become difficult or impossible to restart. 3,540,155 11/1970 Walker 51/9 14 Claims, 11 Drawing Figures F'QM 26 f' A1.

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I28 RONALD D. HAZELWOOD ATTORNEY PATENTEnmlsmu 3797L174 sum 2 or 4 INVENTOR.

RONALD D. HAZELWOOD ATTORNEY PAIENIEHIAR 19 I914 SHEET [1F 4 F/GT /0 l1\"\"ENTOR RONALD D. HAZELWOOD ATTORNEY 1 SHOT CLEANING MACHINE The present invention relates to new and useful improvements in shot cleaning machines of the general character of those shown in U. S. Pat. No. 2,752,732 which issued in July, 1956 to Walker, and in U. S. Pat. No. 3,546,816 which issued to Enegren in December, 1970, and more particularly the present invention pertains to an improved means for regulating the rate of shot feed to the impeller and for preventing the impeller from being overloaded on being stopped.

The paramount object of the invention is to feed shot from a hopper or collecting sump therefor into a rotary impeller at a rate that is a function of the rate of rotation of the impeller, whereby shot is fed to the impeller at a diminishing rate as the latter decelerates to a stop so that very little shot remains in the impeller when the latter has stopped.

Another important object is to provide apparatus for realizing the foregoing object that will be automatic and reliable in operation, that will not require special training for operators, and which will function even when the stopping of the impeller is inadvertent, such as might occur by reason of an electrical power failure when the impeller is electrically driven.

Broadly, the invention involves in a shot cleaning machine, the combination of a rotary shot impeller and rotary feed means for feeding shot to the impeller comprising an impeller casing and a hopper for shot disposed in side-by-side relationship at positions of about the same height, said impeller casing and hopper having interiors that are separated by a vertical wall structure, horizontal drive shaft rotatably extending through the interiors of the impeller casing and the hopper and through the wall separating such interiors, said rotary shot impeller including a plurality of impeller blades mounted on the drive shaft for rotation therewith in the impeller casing, said rotary feed means including a plurality of arms mounted on the drive shaft and radially extending therefrom for rotation therewith in the hopper, and said wall having an opening therethroughaffording communication between the interiors of the hopper and the impeller casing, with said opening being horizontally spaced from vertical alignment with the drive shaft whereby the arms of the rotary feed means tend to urge shot in the hopper toward the opening during rotation of the drive shaft in one direction.

Other objects, features, advantages and aspects of the invention will become manifest during the following description of a preferred embodiment thereof, such description being given in conjunction with the accompanying drawings, wherein:

FIG. 1 is a front elevation of the shot cleaning machine;

. FIG. 2 is an enlarged vertical sectional detail view taken on the plane of the section line 2-2 in FIG. 1;

FIG. 3 is a rear elevational view of the machine;

FIG. 4 is a top plan view of the machine;

FIGS. 5 and 6 are end elevational views of the machine from opposite ends thereof;

FIG. 7 is a vertical sectional view taken upon the plane of the broken sectional line 77 in FIG. 6, with certain hidden details being shown in dashed outline;

FIG. 8 is a fragmentary vertical sectional view of the machine taken upon the plane of the section line 8-8 in FIG. 7; 1

FIG. 9 is an enlarged isometric view of the rotary impeller structure showing the same removed from the drive shaft;

FIG. 10 is a vertical sectional view of the basket taken upon the plane of the section line 10-10 in FIG. 7; and,

FIG. 11 is an enlarged isometric view of one of the removable shot screens for one of the shot sumps.

Referring now to the drawings wherein like numerals designate like parts throughout the various views, a shot cleaning machine 10 embodying the principles of the invention is shown, the same being comprised of a steel housing 12 securely mounted upon a rigid steel frame 14 that includes a base section 16 adapted to rest upon a horizontal supporting surface 18.

As shown best in FIGS. 1 and 7, the housing 12 comprises spaced side walls 20 and 22 that are joined by a rear wall 24. The housing 12 also a top wall .26 and a pair of doors 28 and 30 that are respectively mounted for horizontal swinging movement on vertical hinge pins 32 and 34 whereby the doors 28 and 30 can be swung from the positions shown thereof closing the front of the housing 12 to positions opening the front of the housing 12 and affording access to the interior of the same.

When the doors 28 and 30 are closed, the door 28 overlaps the door 30 so that the door 28 holds the door 30 closed, a marginal portion of the door 30 being engaged and retained between the fixed housing and the door 28. The doors 28 and 30 are releasably retained in their illustrated closed positions by latch means comprising a vertical rod 36 rotatably mounted on the door 28 adjacent the free edge 38 of the latter that is remote from the hinge pin 32. The upper and lower ends of the rod 36 are provided with hooks 40 and 42 that are engaged respectively with eyes 44 and 46 fixed to the frame 14. A laterally extending handle 48 is fixed to the rod 36 whereby the rod 36 can be rotated, when the doors 28 and 32 are closed, to move the hooks 40 and 42 into and to cam against the eyes 44 and 46 to force tight closure of the doors and to prevent their opening. Use of the handle 48 in the foregoing manner results in the handle being disposed nearly flush with the front of the door 30 and the handle is releasably retained in such position by being placed in an L-shaped retainer 50 fixed to the door 30. The handle 48 is sufficiently resilient to accommodate such placement for retention by the'retainer 50.

Toopen-the doors 28 and 30, the handle 48 is flexed free of the retainer 50 and the handle 48 is swung clockwise about the axis of the rod 36 to free the hooks 40 and 42 from the eyes 44 and 46, whereupon the doors 28 and 40 are free to open.

The doors 28 and 30 preferably fit snugly enough against the fixed portions of the housing 12 and with each other as to preclude largely if not entirely the escape of shot from within the housing 12 during operation of the same. If desired or deemed expedient, sealing means in the form of sheet neoprene rubber, not shown, can be securedin a conventional manner to peripheral margins of doors for establishing sealing engagement between the doors and the fixed portions of the housing and between the overlapping portions of the doors.

As best shown in FIGS. 7 and 8, the lower end portion of the housing 12 opens into and is integral with the upper open end of a well or sump structure designated generally at 52 in which there is disposed a shot feeding and impeller means designated generally at 54.

The lower end portion of the housing 12 is defined by downwardly converging side walls 56 and 58 constituting integral and inclined downward extensions of the side walls 20 and 22 that join integrally with upstanding end walls 60 and 62 of the sump structure 52. The rear wall 24 has an integral downwardly inclined rear wall portion 64 joining the inclined side walls and joined to the upper end of a rear or side wall 66 of the sump structure 52. The housing also includes a downwardly and rearwardly inclined front wall 68 that connects the inclined walls 56 and 58 and which extends from the doors 28 and 30 to join the front or side wall 70 of the sump structure 52. It will be understood that the doors 28 and 30, when closed, sealingly seat against the forward portions of the top wall 26 and the inclined wall 68 as well as the forward portions of the side walls 20 and 22 in their function of closing the housing 12.

The sump structure includes a bottom wall 74 peripherally joined to the lower edges of the walls 60, 62, 66 and 70. As best shown in F IG. 7, the lower portions of the walls 66 and 70 are downwardly convergent and provided with access openings 76 and 78, respectively, that are normally closed by plates 80 and 82 secured by releasable fasteners 84.

A pair of spaced, parallel and vertical plates or steel walls 86 and 88 are disposed within the sump structure 52 in spaced parallelism with the walls 66 and 70 of the latter, such walls 86 and 88 having horizontal upper edges 90 at a height somewhat higher than the upper extent of the sump structure 52. The walls 86 and 88 have detachably secured respectively thereto by threaded cap screws 89 a pair of co-extensive hardened steel plates or liners 86' and 88'. The latter are substantially coextensive in size with the walls 86 and 88 and can be considered to be replaceable parts of the walls 86 and 88 as may be necessitated by wear. The liners 86' and 88' preferably project slightly above the walls 86 and 88, and are preferably of multisection character and have vertical junctures such as indicated at 89, whereby only portions of the liners 86' and 88 need be replaced.

As will be appreciated on inspection of FIGS. 7 and 8, the bottom and end edges of the walls 86 and 88 are snugly fitted against and secured, as by welding or the like, to the bottom and end walls 74, 60 and 62 of the sump structure 52.

The arrangement is such that the spaced plates or walls 86 and 88 (and their respective liners 86' and 88') together with the portions of the walls 74, 60 and 62 extending therebetween define in effect an opentopped housing for a rotary impeller designated generally at 92. In the preferred construction, the walls 60 and 62 have hardened liners 92' within the housing and welded thereto for resisting wear. The bladed impeller wheel 92 is comprised of a square hub 94 on which are mounted by fasteners 98 a plurality of radially extending blades 96. It will be noted that the blades 96 are radially offset from alignment with the center of the hub 94, and therefore extend radially from the center of the impeller wheel 92 while being inclined to the radius of the wheel 92.

A horizontal shaft 100 extends perpendicularly and freely through aligned openings in the walls 66, 70, 86 and 90, and is journaled in bearings 104 and 105 carried by the-walls 66 and 70. The shaft 100 is driven to rotate anticlockwise as viewed in FIG. 7 by means of an electric motor 106 mounted on the frame 14, and an endless drive belt 108 entrained over pulleys 110 and 112 fixed to the output shaft 114 of the motor and the shaft 100.

The impeller wheel 92 is disposed within the housing therefor partially defined by the walls 86 and 88 with the shaft 100 extending through an opening 116 in the hub 94. The impeller wheel 92 is fixed against rotation on and axial movement along the shaft 100 by conventional means, not shown, such that the wheel 92 can be removed for repair (such as by replacement of hardened steel blades 96) or replacement as will be understood by those skilled in the art.

The spacing of the walls 86 and 88 from the walls 76 and 78 define a pair of sumps or wells 118 and 120 on opposite sides of the impeller casing or housing (as the latter is partially defined by the walls 86 and 88 and their respective liners 86' and 88).

With the understanding that shot fed into the impeller casing will be propelled upwardly in the housing 12 by the wheel 92 and that such shot upon its kinetic energy being spent will gravitationally descend in the housing 12 with the majority of such gravitationally descending shot falling into the sumps 118 and 120 (in approximately equal amounts) and a minor fraction of such descending shot enters the sump structure 52 between the walls 86 and 88. Such minor fraction of the descending shot is largely contacted immediately by and again propelled upwardly by the impeller wheel 92.

Means is provided for feeding shot that descends into the sumps 118 and 120 to the impeller 92 in such a manner that when the electric motor 106 is deenergized the rate of feed diminishes so that, when the impeller 92 comes to rest, the amount of shot accumulated in the sumps 1 l8 and 120 has increased to a maximum, and the amount of shot immediately engageable by the wheel 92 has been decreased to such an amount that rotation of the impeller 92 can be again initiated by energization of the motor 106 without overloading the latter.

Such feeding means comprises a pair of rotary feeders 122 and 124 disposed respectively in the sumps 118 and 120 and secured to the shaft 100 for rotation therewith. Since the feeders 122 and 124 are identical, a detailed description of the feeder 124 will suffice for both. The feeder 124 is comprised of a metal collar 126 on the shaft, such collar having a pair of diametrically opposed, internally threaded openings 128 therein. A pair of hardened steel bolts 130 and 132 are threaded tightly into the openings 128 to engage the shaft 100 and thus hold the collar 126 fixed relative to the shaft 100. A pair of jam nuts 132 are tightened on the bolts 128 and 130 to engage the collar 126 to hold the parts in assembled relation. It will be evident that the nuts 132 can be loosened and removed so that the bolts 128 and 130 can be removed and replaced when they have become excessively worn. I

The arms or bolts 128 and 130 of both of the rotary feeders 122 and 124 travel to the right as viewed in FIG. 7 on energization of the motor 106. The arrangement is such that the bolts 128 and 130 and particularly the enlarged heads 134 of such bolts engage and tend to move shot, not shown, filling the lower portions of the sumps 118 and 120 to the right as viewed in FIG. 7, that is, toward openings 136 in the walls or partitions 86 and 88 that separate the sumps 118 and 120 from the impeller wheel 92. It will be noted that the openings 136 are elongated vertically, displaced'to the right of the shaft 100 (as viewed in FIG. 7), and are relatively small in their lower extent 138 as compared to their upper extent 140.

After the impeller wheel 92 has been running at full speed for some time the amount of shot in the sumps 118 and 120 is relatively depleted as shot therein is greatly agitated by the arms or headed bolts 128 and 130 and urged toward the openings 136 so as to enter the space between the walls 86 and 88 and be therein picked up and propelled upwardly by the impeller wheel 92. In other words, when the shaft 100 is rotating at full speed, the feeders 122 and 124 maintain a high rate of shot feed from the sumps 1 18 and 120 to the impeller 92 and the quantity of shot in the sumps 118 and 120 is relatively depleted. Such described performance is enhanced by the relatively greater size of the upper portions 140 of the openings 136 than the lower portions 138. This is because the shot turbulence is greatest at higher rotary speed which causes more shot to move about the upper extents 140 of the openings 136 and thusincrease the probability of movement through the openings 136 to the impeller wheel 92.

As the rotary speed of the shaft 100 is reduced, less turbulence and agitation of shot is caused in the sumps by the feeders 122 and 124 even though the amount of shot accumulated in the sumps increases. Indeed, the reduced action of the feeders 122 and 124 accompanying their reduced rate of rotation results in an increasing accumulation of shot in the sumps 118 and 120 so that when rotation of the shaft 100 ceases, relatively little shot is disposed between the walls 86 and 88 on the bottom wall 74.

It is important to note that such shot on the bottom wall 74 between the walls 86 and 88 is disposed predominantly adjacent the openings 136, that is, to the right of the lowermost extent of the travel of the impeller blades 96 as viewed in FIG. 7. This is important for the reason that the character of the engagement of the impeller blades 96 with shot is such that resumption of rotation of the impeller blades 96 tends to cause movement of shot to the right and/or upwardly as viewed in FIG. 7, so that reactive forces on the impeller wheel 92 are sufficiently small that rotation of the impeller 92 can be easily resumed without subjecting the motor to excessive starting overload. Such overloading would obviously be likely to occur if the relationship of the impeller 92 to the shot were different, or if the direction of rotation of the impeller 92 were reversed as the blades 96 would be urging shot against the bottom wall 74 so as to freeze the impeller wheel 92 against turning. The inclination of the blades 96 relative to the wheel radius contributes to the lifting of shot rather than the forcing of the same against the bottom wall 74 that would tend to freeze the wheel 92.

The walls 74, 86 and 88 are preferably hardened.

steel, as are the blades 96 and the headed bolts 128 and 130, to resist the wear caused by shot.

A large reticulated cylindrical drum or basket 150 is mounted for rotation about a horizontal axisin the housing at a position directly above the impeller wheel 92. The basket 150 has axial trunnions 152 and 154 that are journaled through bearings 156 and 158 in the housing side walls 20 and 22.

The basket 150 is driven in rotation by an electric motor 160 that drives a pulley 162 through reduction gearing 164. An endless belt 166 is entrained over the pulley 162 and a pulley 168 fixed on the trunnion 152. The belt 166 is maintained under proper tension by an idler pulley 170 bearing thereagainst; the pulley 170 being carried by an arm 172 pivoted to the housing 12 at 174. The pulley 170 bears against the belt 166 by means of a tension spring connecting the arm 172 to the housing 12.

Means is provided for withdrawing dust, rust flakes and the like from the housing 12. Such means comprises a hooded vent 178 in the rear wall 24 and an exhaust housing 180 on the top of the housing 12 having communication with the interior of the housing 12. The housing 180 includes a discharge duct 182 adapted to be connected to a combination filter bag and suction unit, or the like, not shown.

An instrument and control panel-184 is mounted on the machine 10 and includes suitable switch controls 186 and 188 for the motors 106 and 160.

The basket 150 rotates about an axis perpendicular to and spaced above the shaft 100, and such basket 150 is for the'purpose of containing articles to be cleaned by the impingement of shot thereagainst. The basket 150 includes steel end discs 190 and 192 connected by spaced steel rods 194. A segment of the basket 150 constitutes a door 196 hingedly connected thereto that may be swung from an open position and releasably latched in a closed position by latch structure that includes an operating handle 197. The door 196 is of reticulated character and includes end pieces 198 and 200 that are connected by spaced steel rods 202.

During operation of the machine 10, the basket 150 and its contents are rotated with the latter being subjected to the impingement of shot thereagainst, such shot being thrown upwardly in a divergent fan-shaped pattern by the impeller wheel 92. The major dimension of the generally fan-shaped pattern of shot parallels the axis of rotation of the basket 150 and the spaced rods 194 and 202 forming the cylindrical form of the same so that the entire length of the basket 150 is subjected to shot. A substantial amount of the shot enters the basket 150 unhindered (much of the remainder being deflected by the rods but nevertheless entering the basket 150 with a small loss of kinetic energy) to impinge against and thus clean the articles, not shown, in the basket 150. A deflector plate 204 of hardened steel is mounted on the inclined housing wall in a position to deflect shotthat might pass below and miss the basket into the latter, as shown in FIG. 7. The plate 204 is rigidly mounted, and sufficiently massive, as well as being elastic so that shot (itself steel and of inherent elastic character) so deflected suffers a minimal amount of kinetic energy on being deflected.

If the character of articles being cleaned is sufficiently elastic and of open character as not to pack too densely, the basket 150 can be loaded quite full as little, if any, tumbling of articles need occur for good cleaning of exposed article-surfaces. This is because shot will ricochet back and forth as it penetrates to the region of the axis of the basket. Articles that pack densely or of less elastic character can be more lightly loaded in the basket 150 so as to tumble on rotation of the latter to thereby assure better exposure of the surfaces of the articles-to impingement by energetic shot.

In order to recover and avoid the spillage of shot on the floor that can constitute a severe hazard to good footing by operating personnel, a trough 206 is The tubes 208 and 210 also provide additional ventilation for the previously described dust removal system.

In order to avoid or minimize the possibility of any object substantially more sizable than shot being fed into the impeller wheel 92, a pair of screens 220 and 222 are provided that respectively cover the open upper ends of the sumps 118 and 120. The screen 220 rests upon the inclined wall 64 and the upper end portion of the wall 86, and the screen 222 rests upon the inclined wall 68 and the wall 88. As shown in FIG. 11 with respect to the screen 220, the latter has triangular end flanges having free end apex angles 226 corresponding to the dihedral angle of convergence of the walls 64 and 86. This arrangement affords proper seats for screens 220 and 222. Objects which may be collected on the inclined screens 220 and 222 can be readily observed and easily removed when the doors 28 and 30 are opened.

Attention is now directed to the appended claims.

I claim:

1. In an article cleaning machine of the type wherein shot is cyclically impelled upwardly against and into a rotatably mounted and reticulated article container by a rotary impeller disposed therebelow during rotation of the latter, the improvement comprising said machine being provided with a sump means disposed adjacent the impeller for gravitationally collecting and accumulating spent shot, passageway means communicating between the sump means and the impeller constituting a shot feed inlet for the latter, and rotary feed means operable within the sump means and during rotation of such feed means for urging movement of shot in the sump means toward the passageway means for feeding of such shot tothe impeller, with the rotary feed means being operatively connected to the rotary impeller for concurrent operation therewith, whereby the quantity of shot accumulated by the sump means at any time is a function of prior rotation of the rotary feed means, said impeller being separated from and the sump means being partially defined by a substantially vertical wall, said rotary impeller and said rotary feed means having a common horizontal drive shaft that extends rotatably through said wall, said rotary impeller including a plurality of radially extending blades fixed to the drive shaft for rotation therewith, said rotary feed means including an arm extending radially from and fixed to the shaft for rotation in the sump means, said passageway means being defined by an opening through said wall, with said opening being horizontally displaced in one direction from vertical alignment with said drive shaft, said impeller and said arm defining surfaces of revolution about the drive shaft of respectively greater and lesser diameter, whereby the peripheral velocity of the impeller is substantially greater than that of the feed means.

2. The combination of claim 1, wherein the dimension of the arm in the direction of the extent of the drive shaft is substantially less than the corresponding dimensions of the impeller blades.

3. The combination of claim 1, wherein said opening is vertically elongated and has a vertical length approximating the radius of the surface of revolution of the impeller with the opening having an upper end at about the height of the drive shaft.

4. The combination of claim 1, wherein said opening is vertically elongated and has upper and lower portions respectively of relatively greater and lesser size.

5. In a shot cleaning machine, a housing having an open topped rotary shot impeller means within its lower end portion, said impeller means including a fixed casing having spaced opposite side walls, a horizontal drive shaft rotatably extending through the easing and the opposite sides thereof, impeller blades mounted on the drive shaft for rotation therewith between the opposite sides of the casing, a pair of shot sump means disposed on opposite sides of the casing in positions juxtaposed to the opposite sides of the casing, each of said sump means being partially defined by the housing including downwardly converging side walls, said driveshaft having opposite end portions rotatably extending through both of the sump means and the housing side walls, said sump means having communication with the interior of the impeller casing by means inclusive of each of the opposite sides of the casing having an opening therethrough, with both of said openings being spaced in one direction horizontally from vertical alignment with the drive shaft, each of said sump means being provided with rot'ary shot feeding means therein that comprises a radially extending arm fixed to the drive shaft, and means for rotatably driving the drive shaft to cause the arm to move in said one direction as it radially extends below the drive shaft.

6. The combination of claim 5, wherein each of said impeller blades is forwardly and radially outwardly inclined from the drive shaft with respect to the direction that the drive shaft is driven.

7. In a shot cleaning machine, the combination of a rotary shot impeller and rotary feed means for feeding shot to the impeller comprising an impeller casing and a hopper for shot disposed in side-by-side relationship at positions of about the same height, said impeller casing and hopper having interiors that are separated by a vertical wall structure, a horizontal drive shaft rotatably extending through the interiors of the impeller casing and the hopper and through the wall separating such interiors, said rotary shot impeller including a plurality of impeller blades mounted on the drive shaft for rotation therewith in the impeller casing, said rotary feed means including a plurality of arms mounted on the drive shaft and radially extending therefrom for rotation therewith in the hopper, and said wall having an opening threthrough affording communication between the interiors of the hopper and the impeller casing, with said opening being horizontally spaced from vertical alignment with the drive shaft whereby the arms of the rotary feed means tend to urge shot in the hopper toward the opening during rotation of the drive shaft in one direction.

8. The combination of claim 7, wherein the impeller blades are forwardly inclined in said one direction radially outward from the drive shaft, and means for driving the drive shaft in said one direction.

9. The combination of claim 7, wherein the radial extent of the arms from the drive shaft is substantially less than the radial extent of the impeller blades from the drive shaft, whereby the velocity of the radially outering has its upper end disposed at a height approximaT ing that of the drive shaft 12. In an article cleaning machine of the type wherein shot is cyclically impelled upwardly against and into a rotatably mounted and reticulated article container by a rotary impeller disposed therebelow during rotation of the latter, the improvement comprising said machine being provided with a sump means disposed adjacent the impeller for gravitationally collecting and accumulating spent shot, passageway means communicating between the sump means and the impeller constituting a shot feed inlet for the latter, and rotary feed means operable within the sump means and during rotation of such feed means for urging movement of shot in the sump means toward the passageway means for feeding of such shot to the impeller,

whereby the quantity of shot accumulated by the sump means at any time is a function of prior rotation of the rotary feed means, said rotary feed means being operatively connected to the rotary impeller for concurrent operation therewith, said rotary feed means including a drive shaft, a collar on said shaft having radially outward opening sockets therein that are internally threaded, each of said sockets having removably threaded thereinto an externally threaded arm, each of said arms extending radially from the collar, and a jam nut threaded on each of said arms and tightly bearing against the collar to prevent inadvertent removal of the arms from the collar.

13. The combination of claim 12, wherein the collar has a central opening removably receiving the drive shaft, said sockets opening into the central opening, and said arms having radially innermost ends tightly engaging the shaft in said opening through said sockets'to maintain the collar and the shaft in fixed relation to each other.

14. The combination of claim 13, wherein each of the arms has a radially outermost end that is relatively enlarged. 

1. In an article cleaning machine of the type wherein shot is cyclically impelled upwardly against and into a rotatably mounted and reticulated article container by a rotary impeller disposed therebelow during rotation of the latter, the improvement comprising said machine being provided with a sump means disposed adjacent the impeller for gravitationally collecting and accumulating spent shot, passageway means communicating between the sump means and the impeller constituting a shot feed inlet for the latter, and rotary feed means operable within the sump means and during rotation of such feed means for urging movement of shot in the sump means toward the passageway means for feeding of such shot to the impeller, with the rotarY feed means being operatively connected to the rotary impeller for concurrent operation therewith, whereby the quantity of shot accumulated by the sump means at any time is a function of prior rotation of the rotary feed means, said impeller being separated from and the sump means being partially defined by a substantially vertical wall, said rotary impeller and said rotary feed means having a common horizontal drive shaft that extends rotatably through said wall, said rotary impeller including a plurality of radially extending blades fixed to the drive shaft for rotation therewith, said rotary feed means including an arm extending radially from and fixed to the shaft for rotation in the sump means, said passageway means being defined by an opening through said wall, with said opening being horizontally displaced in one direction from vertical alignment with said drive shaft, said impeller and said arm defining surfaces of revolution about the drive shaft of respectively greater and lesser diameter, whereby the peripheral velocity of the impeller is substantially greater than that of the feed means.
 2. The combination of claim 1, wherein the dimension of the arm in the direction of the extent of the drive shaft is substantially less than the corresponding dimensions of the impeller blades.
 3. The combination of claim 1, wherein said opening is vertically elongated and has a vertical length approximating the radius of the surface of revolution of the impeller with the opening having an upper end at about the height of the drive shaft.
 4. The combination of claim 1, wherein said opening is vertically elongated and has upper and lower portions respectively of relatively greater and lesser size.
 5. In a shot cleaning machine, a housing having an open topped rotary shot impeller means within its lower end portion, said impeller means including a fixed casing having spaced opposite side walls, a horizontal drive shaft rotatably extending through the casing and the opposite sides thereof, impeller blades mounted on the drive shaft for rotation therewith between the opposite sides of the casing, a pair of shot sump means disposed on opposite sides of the casing in positions juxtaposed to the opposite sides of the casing, each of said sump means being partially defined by the housing including downwardly converging side walls, said drive shaft having opposite end portions rotatably extending through both of the sump means and the housing side walls, said sump means having communication with the interior of the impeller casing by means inclusive of each of the opposite sides of the casing having an opening therethrough, with both of said openings being spaced in one direction horizontally from vertical alignment with the drive shaft, each of said sump means being provided with rotary shot feeding means therein that comprises a radially extending arm fixed to the drive shaft, and means for rotatably driving the drive shaft to cause the arm to move in said one direction as it radially extends below the drive shaft.
 6. The combination of claim 5, wherein each of said impeller blades is forwardly and radially outwardly inclined from the drive shaft with respect to the direction that the drive shaft is driven.
 7. In a shot cleaning machine, the combination of a rotary shot impeller and rotary feed means for feeding shot to the impeller comprising an impeller casing and a hopper for shot disposed in side-by-side relationship at positions of about the same height, said impeller casing and hopper having interiors that are separated by a vertical wall structure, a horizontal drive shaft rotatably extending through the interiors of the impeller casing and the hopper and through the wall separating such interiors, said rotary shot impeller including a plurality of impeller blades mounted on the drive shaft for rotation therewith in the impeller casing, said rotary feed means including a plurality of arms mounted on the drive shaft and radially extending therefrom for rotation Therewith in the hopper, and said wall having an opening threthrough affording communication between the interiors of the hopper and the impeller casing, with said opening being horizontally spaced from vertical alignment with the drive shaft whereby the arms of the rotary feed means tend to urge shot in the hopper toward the opening during rotation of the drive shaft in one direction.
 8. The combination of claim 7, wherein the impeller blades are forwardly inclined in said one direction radially outward from the drive shaft, and means for driving the drive shaft in said one direction.
 9. The combination of claim 7, wherein the radial extent of the arms from the drive shaft is substantially less than the radial extent of the impeller blades from the drive shaft, whereby the velocity of the radially outermost extent of the arms is substantially much less than that of the radially outermost extent of the impeller blades.
 10. The combination of claim 7, wherein the opening is vertically elongated and being relatively larger adjacent its upper end.
 11. The combination of claim 10, wherein the opening has its upper end disposed at a height approzimating that of the drive shaft.
 12. In an article cleaning machine of the type wherein shot is cyclically impelled upwardly against and into a rotatably mounted and reticulated article container by a rotary impeller disposed therebelow during rotation of the latter, the improvement comprising said machine being provided with a sump means disposed adjacent the impeller for gravitationally collecting and accumulating spent shot, passageway means communicating between the sump means and the impeller constituting a shot feed inlet for the latter, and rotary feed means operable within the sump means and during rotation of such feed means for urging movement of shot in the sump means toward the passageway means for feeding of such shot to the impeller, whereby the quantity of shot accumulated by the sump means at any time is a function of prior rotation of the rotary feed means, said rotary feed means being operatively connected to the rotary impeller for concurrent operation therewith, said rotary feed means including a drive shaft, a collar on said shaft having radially outward opening sockets therein that are internally threaded, each of said sockets having removably threaded thereinto an externally threaded arm, each of said arms extending radially from the collar, and a jam nut threaded on each of said arms and tightly bearing against the collar to prevent inadvertent removal of the arms from the collar.
 13. The combination of claim 12, wherein the collar has a central opening removably receiving the drive shaft, said sockets opening into the central opening, and said arms having radially innermost ends tightly engaging the shaft in said opening through said sockets to maintain the collar and the shaft in fixed relation to each other.
 14. The combination of claim 13, wherein each of the arms has a radially outermost end that is relatively enlarged. 